Add terminal client, memory, model fallback, version and install improvements

- codecraft: full-screen terminal client (ratatui) – local tools and files,
  models via the CodeCraft server gateway or own providers (standalone with a
  guided setup), slash commands, @files, permission dialogs, resume, update
- Static Linux CLI builds (x86_64/aarch64, cargo-zigbuild) served by the
  server: /cli/install.sh and /cli/download/<target>
- Project memory (remember tool, .codecraft/memory.md) and personal memory
- Model fallback when a host is unreachable or a budget is used up
- Version/commit in UI and health, daily release check, "What's new" dialog
- PWA: install button, maskable icon, manifest id and screenshots
- Case-insensitive detection of connection errors for retries

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/components/settings/CliInstall.tsx

@@ -0,0 +1,44 @@
+import { useT } from "../../i18n";
+import { toast } from "../../dialogs";
+import { Icon } from "../Icon";
+
+/** How to install and use the terminal client. */
+export function CliInstall() {
+  const t = useT();
+  const cmd = `curl -fsSL ${location.origin}/cli/install.sh | sh`;
+  const copy = (s: string) => navigator.clipboard.writeText(s).then(() => toast(t("tokens.copied"), "success"));
+  return (
+    <div className="panel">
+      <h3>
+        <Icon name="terminal" /> {t("cli.title")}
+      </h3>
+      <div className="hint" style={{ marginBottom: 10 }}>
+        {t("cli.intro")}
+      </div>
+      <ol className="cli-steps">
+        <li>
+          {t("cli.step1")}
+          <div className="row" style={{ gap: 6, marginTop: 4 }}>
+            <code className="token-value">{cmd}</code>
+            <button className="small" onClick={() => copy(cmd)}>
+              <Icon name="copy" /> {t("tokens.copy")}
+            </button>
+          </div>
+        </li>
+        <li>
+          {t("cli.step2")}
+          <div className="row" style={{ gap: 6, marginTop: 4 }}>
+            <code className="token-value">{`codecraft login ${location.origin}`}</code>
+            <button className="small" onClick={() => copy(`codecraft login ${location.origin}`)}>
+              <Icon name="copy" /> {t("tokens.copy")}
+            </button>
+          </div>
+        </li>
+        <li>{t("cli.step3")}</li>
+      </ol>
+      <div className="hint">
+        {t("cli.downloads")} <a href="/cli/download/linux-x86_64">Linux x86_64</a> · <a href="/cli/download/linux-aarch64">Linux arm64</a>
+      </div>
+    </div>
+  );
+}